Embodiments of the present invention relate to analog circuits, and more particularly, to differential amplifiers.
A fully differential amplifier provides an output differential signal in response to an input differential signal. A differential signal comprises two signals, where the difference in the two signals contains the relevant information. For example, the input and output differential signals may be voltage signals centered about Vcc/2, within the range [Vss, Vcc] where Vss is a substrate voltage and Vcc is a power rail (or core) voltage.
Fully differential amplifiers find many applications, such as in sensitive, high-speed analog-to-digital converters employing switched capacitor circuits. Furthermore, it is desirable for differential amplifiers to have large gain-bandwidth products, where CMOS (Complementary-Metal-Oxide-Semiconductor) process technology may be employed.